A nanofiber mat comprises metal oxide nanoparticles distributed on surface of metal oxide nanofibers, wherein the nanofiber mat has a surface area at least 150 m2/g, and the metal oxide is selected from titanium monoxide TiOx, wherein 0.65 1, molybdenum suboxide, MonO3n-1, wherein n>1, MonO3n-2, wherein n>1, and vanadium suboxide, VnO2n-1, wherein n>1. Cathodes, anodes and batteries are made using the nanofiber mat. Processes for producing the metal oxide nanofiber mat and an electrode including it are also provided.